Mostly. More of what you're suggesting is here, but don't try to compensate for load, as there are other solutions for that, and you don't want to pooch it if load didn't cause the current condition. Just make it accurate. You can spend beneficial hours watching basic theory and how-to videos by Andy Wyatt, HP Tuners, Andy Whittle, and many more. Pay attention to the goal of the effort (theory), not how they do it in a different system. The why is the important part.Trevor Getty wrote: ↑Mon Jul 05, 2021 1:42 pmBack to voltage correction.
In order to best adjust voltage correction Is it best to turn everything on like fans and lights and create load then adjust the voltage correction until the idle is similar to what it was before or even a bit higher to cope with the extra load?
Nope. You chose the correct table (Base Tune), and simply need to mod that one to your requirements before you begin mapping it. More or less RPM range, more MAP range, and move the incremental header spacing to where the engine needs it most. Burn that. Then, either populate the table with values using the Table Generator (select Use Existing X & Y Bins), or begin with a generic "wedge" table. More about that here. Some begin with a "flat map" of all rich values to get running, such as 60 or 80 VE in every cell.
I don't want to sound repetitive (though I am), but I'll say again that the "tune" is your settings and options, but also contains the tables. A "base tune" is most useful for those settings to get started, but the tables should always be unique to your engine, components, specific fuel, performance goals, etc. I strongly recommend (and you can search other rants) that you do not use someone else's tune on your project.
More often than not, some settings or options (and always the tables) will be incorrect for your specific project, and you'll spend more frustrating time finding and fixing those, than doing it right for your project the first time. It takes time, but when you're done you'll have learned what they are for and that they are correct for your setup, in its current configuration.
That's the idea. What you call a Base Tune is just the best settings and options for your project, so the dyno and log data can aim you at best performance, for timing, fuel and Lambda/AFR targets.Trevor Getty wrote: ↑Mon Jul 05, 2021 1:42 pmOk onto base tuning.
Now that I want to create a base tune before taking it to the rolling Road.
IS it best practice to leave afr table 'as is' and instead tune the car without afr correction initially. So use different rev points until its MBT I think it was called. Ie map stops falling and rpm stops climbing and dial it back one or 2 degrees? Then if the fuel doesn't match the afr increase the fueling I could use auto tune features or adjust manually and then go through same process again checking ignition timing?
Random: Use whatever methodical methods that you can wrap your head around, and stick to them. Make one change at-a-time and check results. Use all your data to see the big picture (and little influences) as diagnostics for what to change when tuning and why.
A running tune good enough to drive to the dyno (or off the trailer) is your goal at this point. If it were street tuning, then you'd be testing without corrections for good AFRs to use as targets. For dyno work, you can just use gross guesses and VEA (auto-tune, but not Live while you drive!) to bring the table generally into a safe running shape. Some just plug (gasoline) 13:1 (Lambda 0.87-ish) everywhere on the AFR Target table, wire or check-valve the wastegate open, and drive it around the block. It sucks for performance, but is safe and drives, and is ready for the dyno when it gets there.
Tune from the bottom-up. Begin with idle, and work your way up through off-idle, light cruise, light accel, etc. As you go, you will see a pattern develop for timing and fuel, and friendly Lambda. By the time you're pushing it hard, you'll already have a good idea of what it will want when you get there. Enough for now, and don't let anxiety, time, or enthusiasm push you into areas you or the engine are not ready for.
Ah, because "turbo". Seriously, there can be a few reasons. One is that the burn rate is truly increasing due to boost pressure and turbulence, and therefore the timing must be retarded in order to maintain the best peak cylinder pressure crank angle (minimum spark timing for best torque or the spark timing for maximum brake torque or MBT). Or, it is due to det-limited pump gas, and they are delaying the pressure curve to avoid det (but, what fuel and is yours similar?). A related possibility is that they are adding "insurance" in-case the customer tanks-up with crappy fuel and doesn't test for det before beating on it. Unfortunately, this means the engine is running de-tuned for a hopefully-never "if" situation.
While we can't always know, it can also be that the ECM did not have ignition latency correction, so retard is less than actual, or it could be right-on. All of this points to the mantra that the tune for your project is unique, and should be tuned on its own merits and many factors. Use care if "borrowing" tune info, as you can't know what those tuners were doing or thinking when they clicked their mouses. Have fun!